1. Field of the Invention
The present invention relates to a method apparatus for controlling an output voltage of an ultrasound signal in such a way that a probe outputs a target output voltage in consideration of characteristics information of the probe and transmission conditions of an ultrasound system.
2. Description of the Related Art
An ultrasound diagnostic device is a device for transmitting ultrasound signals from a surface of a target object toward a predetermined region inside the target object and acquiring tomograms of soft tissues or images of blood flow based on information regarding ultrasound signals reflected by tissues inside the target object.
Advantages of such an ultrasound diagnostic device are its small size, inexpensive price, and real-time result acquisition. Furthermore, an ultrasound diagnostic device is very safe and causes no radiation exposure. Therefore, an ultrasound diagnostic device is widely used together with other types of imaging diagnostic devices, such as X-ray devices, computerized tomography (CT) scanners, magnetic resonance image (MRI) devices, scintillation cameras, etc.
Generally, outputs (transmitting voltage, pressure, and energy) of an ultrasound diagnostic device are restricted and determined based on the international standards (e.g., mechanical index (MI)). In this regard, the MI is an index that represents quantified mechanical effects of ultrasound on a human body.
Another related international standard is a thermal index (TI). Generally, the internationally permitted levels of the MI and TI are less than 1.9 and less than 6.0, respectively.
Meanwhile, an ultrasound diagnostic device is configured to output ultrasound signals having power levels that are optimized to applications without exceeding limits set by the FDA based on results of AP&I experiments. However, in some applications, e.g., a low MI environment utilizing a blood-pool contrast agent, the level of an output voltage may be changed or distorted.